Portable frame-and-sail assemblies are widely used for skate sailing and hang gliding, and are used for small boat, iceboat and land vehicle sailing. Such assemblies characteristically comprise a multiple number of full width spars, i.e. one at the leading edge, one near the lift center for being manually grasped, and sometimes one at the foot of the sail. Unlike kites, parachutes or sails used only for running with the wind, a sail for running cross-wind or to windward, possibly at speeds of from two to three times wind velocity, is required to be rigged with the leading edge stayed for damping vibration, a non-pliant member such as a mast being used if possible, and if not, then a tautly stretched, strongly anchored stay line as may be used for a jib. A skate sail, which is manually held at an oblique angle during use, is optimumly provided with a head spar. Whether the sail is tensioned tautly for running close to the wind or is provided with slack for running with the wind, a simple cruciform frame sufficiently stout to provide adequate anchorage for rigging a stay line proves excessively heavy for use in a skate sail, in which weight is a factor limiting the ability and endurance of a skater to support and manipulate a sail assembly. Reducing the number and size of framing members in a skate sail to enable use to be made of fewer, shorter and thinner members increases the serviceability of a sail for such use.